activities, which were great, we will pass over, and deal only with his literary interests, as they are revealed in his letters and in other sources. The letters most instructive from this point of view are mostly written from Bobbio. To Archbishop Adalbero of Rheims he says (Ep. 8), "Procure me the history of Julius Caesar from Adso, Abbot of Montièrender, to be copied, if you want me to furnish you with what I have, viz. the eight books of Boethius on Astrology and some splendid geometrical diagrams." To Abbot Gisalbert (Ep. 9): "The philosopher Demosthenes wrote a book on the diseases and treatment of the eyes, called Ophthalmicus. I want the beginning of it, if you have it, and also the end of Cicero pro rege Deiotaro." Rainard, a monk, is asked for M. Manlius De astrologia (who is thought by Havet not to be the poet Manilius, but Boethius) and for some other books. Stephen, a Roman deacon, is to send Suetonius and Symmachus. "The art of persuasive oratory (Ep. 44) is of the greatest practical utility. With a view to it I am hard at work collecting a library, and have spent very large sums at Rome and in other parts of Italy, and in Germany and the Belgian country, on scribes and on copies of books." To a monk of Trèves (Ep. 134): "I am too busy to send you the sphere you ask for: your best chance of getting it is to send me a good copy of the Achilleis of Statius." The monk sent the poem, but the sphere was again withheld. Such extracts shew the catholicity of Gerbert's tastes. Richer tells the same tale; he runs through the Seven Liberal Arts, and shews what methods and books Gerbert used in teaching each of them. In Mathematics his chief innovation seems to have been the revival of the use of the abacus for calculations, and the employment, in connexion with it, of an early form of the "Arabic" (really Indian) numerals from 1 to 9, without the zero. He also wrote on mathematical subjects, though, perhaps, no signal discovery stands to his credit. Besides all this he was a practical workman. William of Malmesbury describes in rather vague terms an organ made by him which was to all appearance actuated by steam. To the same excellent author and to Walter Map we owe all the best of the many legends that have gathered about Gerbert; of the treasure he found at Rome, guided to it by the statue whose forehead was inscribed "Strike here," of the fairy whom he met in the forest near Rheims, and of his death. He, like Henry IV of England, was not to die but in Jerusalem. His Jerusalem was the basilica of Sta Croce in Gerusalemme at Rome. It may be worth while to end this sketch of him with a correction. We are commonly told that the sixth or seventh century uncial manuscript of the Scriptores Gromatici, the Roman writers on land-measurement, which is now at Wolfenbüttel, and is known as the Codex Arcerianus, was Gerbert's. This is denied by his latest editor, Boubnov, though he allows that the book was at Bobbio in the tenth century.
Our last topic is that of books in vernacular. For practical purposes
